edthecynic
Censored for Cynicism
- Oct 20, 2008
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UHI is not a trend. UHI artificially raises the average temperature the trend is measured against therefore artificially lowering the trend. You can't admit it because that would end your conspiracy theory!Actually, it takes a convoluted rationalization to convince yourself that the UHI effect can actually raise temperature ANOMALIES since you actually acknowledge it raises temperature readings. Since anomalies are measured against the average temperature readings over 30 years, higher temperature readings yield a higher average the anomaly is measured against and therefore a lower anomaly. Since it is anomalies that show trends over time, the UHI effect lowers the trend and when corrected for will mathematically raise it.A few years ago I read the Hansen and Seto (?) paper on UHI and their method of correcting for it. it was bizarre and seemingly without commonsense. the end result was roughly half of the sites were raised, half lowered, for a net result of nothing.
it takes a whole lot of convoluted thinking to convince yourself (or anyone else) that urban heat island effect can actually lower the temperature readings so that they need to be artificially raised.
Common sense is the collection of prejudices acquired by age eighteen.
- Albert Einstein
sorry, not buying that. UHI is a trend. airports add new runways, small buildings are replaced with bigger ones. greenspace gets built on and roads are paved, all in a steady progression (ok, I guess Detroit is an exception). if there was no other trend besides UHI then you would be lowering recent temps and raising old ones. in fact we see the exact opposite adjustments with recent temps raised and the past cooled. it does not matter what the other trends in temperature are, up or down, the correction for UHI is to lower the trend for all areas that are growing.